STEP-COVID: a pilot study of a prenatal intervention for pregnant women during the COVID-19 pandemic

The COVID-19 pandemic has been associated with a global increase in psychological distress in pregnant women. This study evaluated the effects of STEP-COVID, a six-session mentalization-based prenatal group program offered online during the COVID-19 pandemic. The 100 participants were allocated to STEP-COVID or to the natural trajectory of prenatal care. Pre- and post-intervention assessments included measures of psychological distress, post-traumatic symptoms and positive affectivity. Perception of change during pregnancy on resilience-promoting factors was also assessed at post-intervention. A significant decrease in psychological distress and post-traumatic symptoms and an increase in positive affectivity were observed in participants in the intervention condition, whereas only post-traumatic symptoms improved in the control condition. Women who participated in STEP-COVID also reported greater changes during pregnancy on resilience-promoting factors than women in the control condition. Results hold promise for buffering the effect of the pandemic on the mental health of pregnant women using brief online interventions. Clinical trial registration: NCT05419167 (15/06/2022)

www.nature.com/scientificreports/ improving mentalization and emotion regulation during pregnancy would have multiple positive outcomes for mothers, their infant, and the mother-infant relationship in times of heightened stress such as the COVID-19 pandemic, the general goals of the STEP-COVID program are to foster emotion regulation and reflective capacities. More precisely, the program aims to (a) support mentalization in relation to oneself, motherhood and the relationship with the child to be born, (b) reduce isolation by allowing participants to exchange about the positive aspects and the challenges of pregnancy and motherhood with other women, (c) explore what pregnant women are going through in the context of the pandemic, (d) allow participants to repossess their experience of pregnancy during this period of insecurity and fear, and (e) consider new ways of coping with stress and unpleasant emotions. The program is manualized and uses structured activities based on theoretical grounds and empirical research during which facilitators share information, animate reflective activities, and facilitate exchanges. The intervention is divided into two phases, each including three sessions. The first three sessions aim to explore how the participants feel (making sure to pay attention to both pleasant and unpleasant emotions), to better understand what makes them feel this way, to allow them to exchange with other people who are going through similar experiences, and to support the ability to manage stress and more unpleasant emotions in order to find or maintain a sense of balance. The following three sessions aim to enable participants to refocus on their experience of pregnancy and motherhood by giving them the opportunity to reflect upon how they wish to be as mothers, upon how their personal history influences their experience of pregnancy and motherhood, upon the moments that, as mothers, might be the most pleasant and those that will require more adaptations, and upon identifying the needs they have or expect to have after childbirth as well as the resources available to them to meet these needs. The intervention is inspired by mentalization-based practices and invites participants to reflect upon the thoughts and emotions underlying their behavior and to develop a similar aptitude with regard to their child to be born.
The objective of the current study was to evaluate whether STEP-COVID could contribute to mitigating psychological distress and post-traumatic symptoms, increase positive affectivity, and contribute to positive changes in self-perception, relationships with significant others, and resilience (defined as perceiving oneself as being competent in the face of challenging life circumstances).

Methods
Recruitment strategy. Participants were recruited through advertisements at pregnancy-related medical appointment centers or on social media during the COVID-19 pandemic between September 2020 and May 2021. Participants who expressed interest in learning more about the study were contacted by phone or email by a research assistant who explained the research protocol and briefly presented the interventions. Two versions of the intervention were simultaneously offered by the research team: the original STEP program (i.e., eight to nine intervention sessions developed for pregnant women who experienced childhood traumas) and STEP-COVID. The first stage of the study consisted in completing a series of questionnaires online on a secure platform to collect baseline data for the evaluation of the program and to assess the eligibility criteria. Most measures were re-administered toward the end of pregnancy. The study received ethical approval from our University Ethics Committee (CER-16-226-10) and from the Institutional Review Board of our regional health center (CER-2016-016). All experiments were performed in accordance with relevant guidelines and regulations. The clinical trial is registered under number NCT05419167 (15/06/2022).
Group assignation. Intervention arm. The study used a non-randomized clinical trial. Women who met the eligibility criteria based on baseline assessments (i.e., being between 12 and 28 weeks of pregnancy and being available when the program was scheduled) were invited to participate in the program. Since having experienced childhood traumas was not an exclusion criterion for participating in STEP-COVID, participants who reported having been exposed to childhood traumas at baseline assessment were invited to participate in the original program especially develop for trauma-exposed women, but were ultimately free to choose the version of the program they wished to participate in. Women interested in the STEP-COVID Program underwent a brief interview on a secure video teleconferencing platform during which the program was introduced, the conditions for participation were clarified (i.e., being able to ensure confidentiality during the meetings) and further exclusion criteria were assessed (i.e., presenting difficulties that compromise the emotional and reflective availability required by the program such as suicidal ideation, active violence, mental health disorders not stabilized, significant drug or alcohol use, self-destructive behavior, not being convinced of carrying the pregnancy to term, or experiencing a high-risk pregnancy). Twenty-three pregnant women were allocated to the intervention arm of the study (see Fig. 1).
Control arm. Women who could not participate in the intervention, because no group was offered at that moment or because they were unavailable when groups were scheduled, were assigned to the control arm of the study. These women did not engage in any of the STEP programs and received the regular trajectory of prenatal care (e.g., prenatal classes). Seventy-seven pregnant women were allocated to the control arm of the study (see Fig. 1). They completed the same baseline and post-intervention assessments as participants in the intervention arm at the same moment of pregnancy (see Table 1).

Measures. Demographic and historical variables.
Women self-reported on age, parity, marital status, education level, race/ethnicity, and annual household income at the baseline assessment. They also completed the Childhood Trauma Questionnaire (CTQ) 26 . The CTQ includes 28 items rated on a 5-point Likert scale from 1 (never true) to 5 (very often true) and assesses five types of traumas with validated cut-offs 27  www.nature.com/scientificreports/ least one subscale above the cut-off were classified as having been exposed to childhood trauma. The CTQ shows good validity across clinical and general populations 26 . In this study, Cronbach's alpha is 0.82.
Evolution of mental health symptoms. Maternal mental health symptoms at baseline and post-intervention time points were assessed using three questionnaires. First, the 10-item Kessler Psychological Distress Scale (K10) assessed psychological distress using a 5-point Likert scale from 1 (none of the time) to 5 (all of the time) 28,29 .
Higher scores indicate greater distress. The K10 has adequate sensitivity and specificity for the screening of mood and anxiety disorders in pregnant women 30 . In this study, Cronbach's alpha is 0.91 (at both baseline and post-intervention). Second, given that the COVID-19 pandemic may represent, for many, a form of trauma due to its threatening, unpredictable, extreme, and prolonged nature 31,32 , and since an increase in symptoms of post-traumatic stress disorder (PTSD) was observed in pregnant women during the pandemic 33 www.nature.com/scientificreports/ symptoms before and after the intervention was assessed using the PTSD Checklist for DSM-V (PCL-5) 35,36 . Its 20 items are rated using a 5-point Likert scale from 0 (not at all) to 5 (always). Higher scores indicate more symptoms. Both the French and original English versions have equally adequate validity and reliability 35,37 , and the instrument has been often administered to pregnant women 38,39 . In this study, Cronbach's alpha are 0.92 (baseline) and 0.91 (post-intervention). Finally, positive affectivity was assessed using the Positive Affect subscale of the Positive and Negative Affect Scale (PANAS) 40,41 . The 10 items of the positive affect scale are rated on a 5-point Likert scale from 1 (very slightly or not at all) to 5 (extremely). Higher scores indicate more positive affectivity such as enthusiasm, energy and dynamism. Both the French and original versions show good psychometric properties 40,41 . In this study, Cronbach's alpha are 0.82 (baseline) and 0.85 (post-intervention).
Perception of change during pregnancy on resilience-promoting factors. Perception of change during pregnancy was assessed at the post-intervention follow-up using two questionnaires. First, positive changes in the aftermath of stressful events were measured using the Post Traumatic Growth Inventory (PTGI) 42,43 . Its 21 items are rated on a 6-point Likert scale, from 0 (I did not experience this change) to 5 (I experienced this change to a very great degree). In this study, participants were asked to complete the questionnaire regarding changes since the beginning of pregnancy. The PTGI has five subscales reflecting different constructs: New Possibilities, Relating to Others, Personal Strength, Appreciation of Life, and Spiritual Change. Both the French and the original versions are valid and reliable for measuring post-traumatic growth 42,43 . In this study, Cronbach's alpha is 0.96.
Finally, changes in domains of functioning were assessed using a homemade questionnaire (Changes in domains of functioning during pregnancy) 44 . Its 19 items are rated on a 5-point Likert scale, from 1 (Greatly deteriorated) to 5 (Greatly improved). The instrument yields three subscales: Self-Perception, Relationship with Partner, Relationship with Others. In this study, Cronbach's alpha is 0.93. Data analytic strategy. Statistical analysis was performed using SPSS version 27. Baseline differences between treatment and control groups were assessed using independent samples t tests and chi-square tests. Differences between baseline and post-intervention on psychological distress, post-traumatic symptoms and positive affectivity were assessed using paired-sample t tests run separately for the Intervention and Control arms. Differences between the Intervention and Control groups on resilience-promoting factors were assessed Table 1. Demographic and clinical characteristics of all women enrolled in the study who completed baseline data (N = 268). a Participants were included in the study if they showed some interest in the intervention. b Participants were excluded from the present study when they refused to partake in the intervention protocol but accepted to complete research assessments. c Two-sided p-values were obtained from t-tests for continuous variables and Chi-square tests for categorical variables. d Nine participants did not report annual household income and eight participants did not complete baseline assessment of childhood trauma (missing data). Informed consent. Informed consent was obtained from all individual participants included in the study.

Results
Demographics. As a preliminary analysis, we compared participants who showed some interest in the intervention (n = 127) to participants who were not interested in participating in the program (n = 142) on baseline demographic and clinical data (see Fig. 1 and Table 1). Overall, participants who were not interested in the program were more frequently multiparous (n = 66, 46.5%) than women who showed interest in the intervention (n = 36, 28.6%), χ 2 (1) = 9.65, p = 0.002, and reported lower post-traumatic stress symptoms, t(248) = 2.22, p = 0.03. However, participants from both groups did not differ in terms of sociodemographic variables as well as baseline psychological distress and positive affectivity. Women allocated to the Intervention and Control arms and who provided complete post-treatment followup were balanced on baseline sociodemographic variables, exposition to childhood interpersonal traumas and mental health symptoms ( Table 2). Participants were mainly married or in common-law relationships with the other parent (n = 51, 98%), had some post-secondary education (n = 49, 92.4%) and were not part of a racial minority (n = 50 White/Caucasian, 96.2%). Median household annual income was around C$95 000 which represents a sufficient income for a family.  Table 2. Baseline participant characteristics of women who provided complete post data (n = 52). c Two-sided p-values were obtained from t-tests for continuous variables and Chi-square tests for categorical variables.   Table 3, women who completed the STEP-COVID program observed greater changes during pregnancy on resilience-promoting factors than non-participating women. More precisely, they reported feeling more capable of overcoming difficulties (d = 0.68), witnessing positive changes in their self-perception (d = 0.63) and observing positive changes in their relationship with their partner (d = 0.74). Participation in STEP-COVID was not associated with a greater appreciation of life, a greater appreciation of social support, the discovery of new life opportunities, or better relationships with significant others (excluding the partner).

Discussion
The COVID-19 pandemic has intensified the need for rapid research and novel clinical interventions 21 . This is particularly true for pregnant women, given the well-documented effects of prenatal distress on maternal functioning and offspring development 13,[18][19][20] . However, intervention research is slow [45][46][47] and rare are the  Table S1. * p < 0.05; n.s. = non-significant. www.nature.com/scientificreports/ empirically-supported interventions to buffer the deleterious impact of the COVID-19 pandemic on the mental health of pregnant women worldwide. Our findings that a brief online intervention could contribute to mitigating psychological distress and post-traumatic symptoms, increasing positive affectivity, enhancing resilience, improving the quality of the relationship with the partner and supporting a more positive view of self in pregnant women during the COVID-19 pandemic has important implications for clinical practice and public health. The results also offer additional support concerning the acceptability of STEP programs 48,49 and the effectiveness of mentalization-based interventions during the prenatal period 22,[50][51][52] .
The results of the study need to be considered in the light of some limitations. First, the sample size was small and participants were not assigned randomly to either the intervention or control conditions. However, conducting an RCT with a large sample size would take significant time and, as recently argued by Venta et al. (p. 202): "If the typical stages of intervention development or adaptation are undertaken prior to making efforts to support infants born during the COVID-19 pandemic and their mothers, we will be too late, missing the most plastic period of child development and one of the most vulnerable periods of a mother's life" 21 . Another limitation is that the program is relatively brief and probably did not meet the needs of all participants. Further research, using mixed-methods and a larger sample of women participating in STEP-COVID should evaluate whether some participants might not improve in the course of the program, investigate the characteristics of these poor responders and clarify their unmet needs. Finally, the exclusive reliance on self-reported measures is another limitation and further studies should use structured clinical interviews, incorporate biological measures (e.g., inflammation) and evaluate whether the intervention contributes to mitigating the recently documented effect of prenatal stress during the COVID-19 pandemic on infant development 16 .

Conclusion
Our findings have immediate implications for clinical practice. First, around half of the pregnant women who were approached during the recruitment process showed interest in participating in the program (see Fig. 1). This suggests that implementing and making accessible such psychological interventions on a large scale would successfully reach many pregnant women from the community and would respond to a definite need in this population. Second, the STEP-COVID program appears as an interesting avenue for a large-scale deployment. Indeed, the program is relatively brief (six-sessions), manualized, designed to be offered online, and the current pilot data support its effectiveness.

Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.